The solar wind is
a continuous outward stream of particles (mostly protons and
electrons) from the sun’s hot corona. Energized by high
temperatures in the corona, these particles leave the sun at
speeds ranging from 200 to
500 miles per second (300 to 800 kilometers per second). The
fastest of these particles stream out through the middle of coronal
holes.

Because the sun rotates, the departing solar wind takes on a pinwheel
shape when viewed from above. Embedded in this particle pinwheel
are magnetic fields that get dragged into interplanetary space.

The solar wind can be strongly affected by
solar flares and coronal
mass ejections, both of which fling
huge amounts of coronal material and embedded magnetic fields
into space. These ejected particles become a powerful “gust” in
the solar wind. When they reach the earth, they can cause severe
space weather storms.